Format

Send to

Choose Destination
Am J Physiol Cell Physiol. 2002 Feb;282(2):C302-9.

Changes in Na(+)-K(+)-ATPase activity influence cell attachment to fibronectin.

Author information

1
Department of Woman and Child Health, Karolinska Institutet, 171 77 Stockholm, Sweden.

Abstract

Most vital cellular functions are dependent on a fine-tuned regulation of intracellular ion homeostasis. Here we have demonstrated, using COS cells that were untransfected or transfected with wild-type rat ouabain-resistant Na(+)-K(+)-ATPase, that partial inhibition of Na(+)-K(+)-ATPase has a dramatic influence on cell attachment to fibronectin. Ouabain dose-dependently decreased attachment in untransfected cells and in cells expressing wild-type Na(+)-K(+)-ATPase, but not in cells expressing ouabain-insensitive Na(+)-K(+)-ATPase, whereas inhibition of Na(+)-K(+)-ATPase by lowering extracellular K(+) concentration decreased attachment in all three cell types. Thirty percent inhibition of Na(+)-K(+)-ATPase significantly attenuated attachment. Na(+)-K(+)-ATPase inhibition caused a sustained increase in the intracellular Ca(2+) concentration that obscured Ca(2+) transients observed in untreated cells during attachment. Inhibitors of Ca(2+) transporters significantly decreased attachment, but inhibition of Na(+)/H(+) exchanger did not. Ouabain reduced focal adhesion kinase autophosphorylation but had no effect on cell surface integrin expression. These results suggest that the level of Na(+)-K(+)-ATPase activity strongly influences cell attachment, possibly by an effect on intracellular Ca(2+).

PMID:
11788341
DOI:
10.1152/ajpcell.00117.2001
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Atypon
Loading ...
Support Center